One high-leverage strategy rooted in a strong research base--the revitalized tutoring center--provides a wealth of opportunity to students who may be otherwise underserved. This embedded, open-all-day tutoring center supports collaborative teacher teams by using peer tutors and community volunteers. By centralizing resources and providing supports during the school day, free to all students and targeted to some, the center helps schools close the opportunity gap without overburdening teachers, schedules, or budgets. One high school in Colorado that implemented the approach experienced a dramatic improvement in on-time graduation rates.